Coated concrete



I March 7,' 933.

. P.'J. MAUL Er'AL f y 1,900,833

l GOAT-.3D CONCRETE Filed oct. 10, 195o Patented Mar. 7, 1933 UNITED NSTATES PATENT ori-Ica PETER J. IAUL, F DETROIT, MICHIGAN, AND MARTIN HOFFMAN, 0F CHICAGO, ILLINOIS i conm coNcranrn Applicaties: led october 10, 1930. Serial No. 487,879.

This invention relates to coated concrete, and a method ofy producing it, and the primary object of the invention is to provide concrete having an improved waterproof coating which, in some instances, is also employed for ornamental purposes. The term concrete is employed generically to include concrete which is formed from cementitious material and various aggregates such as gravel, crushed stone,- sand,

cellular burned shale, cinders, granular cellular slag, etc. Concrete embodying the invention is provided-with a coating which is sprayed there, on in a fused state. In practicing the imy proved method, the coating material is re' duced to a powder, and this powder is sprayed on the concrete in'an Oxy-acetylene iame, or the equivalent for the purpose. In

one embodiment of the invention, the powdered coating material is advanced to the Oxy-acetylene flame in a tube of cellulose, lead, or any other suitable substance, and in another embodiment of the invention the powdered coatin vmaterial is formed 'into a ribbon or strand by combining it with a binder. In the latter form, the ribbon or strand of powderedcoating materialis advanced intoy the ame which fuses the coating material and either fuses or burns up the binder.

In certain embodiments of the invention, coating or glazing material is incorporated in the concrete so that when the Oxy-acetylene ame, or the equivalent, is directed thereon the` coating or glazing material on the surface ofthe concrete will fuse. Additional coating material is'preferably sprayed upon the concrete through the Oxy-acetylene flame and this combines with the coating material exposed on the surface of the concrete.

In the drawing: Y V Figure 1 is f a perspective view, partly broken away, of a coated concrete block which embodies the invention.

Fig. 2 is a somewhat diagrammatic section taken through an Oxy-acetylene torch comprising means for spraying powdered coating material on concrete.

Fig. 3 is a perspective view of a tube filled 5o with powdered coating material, and

Fig. 4 is a perspective view of a strand of powdered coating material which is held in strand form by a binder.

In Fig. 1, a coated block of concrete embodying the invention is shown, the block being one ofthe type commonly employed in building construction, etc. It is to be understood, however, that the invention is not limited to this use as the invention may be employed in lighting posts, poles for telephone and power wires, shingles, rooting tile, roofing slabs, garden furniture, Statuary, collins, and in any other articles which are formedA from concrete.

The block shown in Fig. 1 comprises a body portion 10 and a coating 11. The body portion 10 may be made of cementitious matel' rial and any suitable aggregate such4 as gravel, crushed stone, sand, cinders, granular slag, or the like, but in the preferred embodiment of the invention cellular burned shale is employed as the finain or principal aggregate. One form of cellular burned shale suitable for this purpose is known as Haydite and this is preferably employed. The body portion 10 also comprises lfinely divided coating or glazing material for a purpose which will presently appear.

The coating 11 is formed by spraying coat- 80 ing material .on the body portion 10. The

coating material may comprise substantially any commercial glaze. Among the materials that may be employed are feldspar, alumina, lead and alkali glazes. One glaze which is particularly suitable for the purpose comprises 258 iparts by weight of white lead, 51.6 parts o Kaolin and 7 2parts of flint, and another glaze particularly suitable for the purpose comprises 154.8 parts by weight of white lead, 30 parts of calcium carbonate, 55.7 parts of eldspar, 25.8 parts of Kaolin and 48 parts of flint, these materials being in powder form.

Any suitable apparatus may be employed for spraying and fusing the powdered coating material, but the powdered material is preferably sprayed through an Oxy-acetylene flame, or the equivalent. In Fig. 2, an Oxy-acetylene torch `15 is shown, which torch comprises a nozzle 16 and tubes 17 and 18 which communicate with sources of compressed oxygen and acetylene gas, respectively. The oxygen and acetylene gas are mixed in a mixing chamber 19 and as the gaseous mixture passes to the nozzle 16 it draws the coating powder 20 from a receptacle 21 which is carried by the torch. The powder is drawn into the torch through a tube 22 which 'proj ects from the receptacle 21. When the powdered material is sprayed onto the concrete, it fuses either in the lame or on the concrete, depending upon the temperature of the flame and upon the materials from which the coating is made. Suiicient material is sprayed onto the concrete to give a coating of the desired thickness.

In another embodiment of the invention, the coating material, in powdered form, is encased in a flexible tube. Thus, in Fig. 3, powdered coating material 25y is shown encased in a flexible-tube 26 which has, preferably, a very thin wall. The tube 26 may be made of any suitable material, and among the materials contemplated vfor this purpose are lead and cellulose. Thus, cellulose tubing formed from viscose extruded through an annular orifice and regenerated may be stu'ied with the powdered coating material and advanced into an Oxy-acetylene dame to be sprayed thereby onto the concrete.

Atnother embodiment o the invention is illus'trated in Fig. 4, wherein we have shown a strand 27 comprising powdered coating material mixed` with a suitable binder. Binders employing such materials as glycerine, sodium silicate, litharge, and the like, are suitable for this purpose. 'Ihe strand 27 may be advanced into an Oxy-acetylene llame, or

- the like, and sprayed thereby onto the concrete, the powdered coating ,material being fused either in the flame or upon the concrete.

As indicated above,coating material is preferably mixed with the aggregrate and cementitious material orming the body portion 10. The coating material for this purpose preterably comprises powdered eldspar, ground glass, borax, or the like. rlhe coating material constitutes. about 10% of the concrete. Then when the coating material is applied to the outer surfaces of the block by an oxyacetylene dame, or the like, the coating material which is part of the concrete mixture and is exposed on the surfaces of the block, fuses and combines with the powdered coatsuch as zinc, copper, brass, or the equivalent, for forming the coating 11. The finely divided metals may be sprayed onto the concrete in the same manner as the powdered y glazes described above, and it is to be understood that the appended claims should be construed to include the use of finely divided metals as coating material unless it is otherwise indicated. 7

As indicated above, the aggregate employed in the concrete is preferably Haydite which is a cellular burned shale. Cellular burned shale is light in weight and does not disintegrate or fuse when subjected to relatively high temperatures, its fusing temperature being approximately 2100o F. In other embodiments of the invention, granular cellular slag from blast furnaces may be employed. -This cellular vitrified slag is dis charged from the blast furnace at a temperature of about 3000 F. and is water cooled so that it becomes relatively cellular and light in-weight. One product of this character is sold under the trade name Pottsco,

It is readily understood that the coatings embodying the invention may be made in various colors' by employing suitable materials. Ornamental eliects may beobtained in y.

various ways. Thus, coatings of diii'erent colors may be applied tothe same surface to y give a variegated eiect.

While we have shown and described certain embodiments of our invention, it is to be understood that it is capable of many modi- 'ications.- Changes, therefore, in the construction and arrangement may be made without departing trom the spirit and scope of the invention as disclosed in the appended clanns, in which it 1s our intention to claim all novelty inherent in our invention as broadly as possible, in view of the prior art.

What we claim as new, and desire to secure by letters patent, is:

1. yAn article formed from concrete having a glaze on a surface thereof formed from kglazing material mixed in the concrete.

- 2. An article formed from concrete having a glaze on a surface thereof formed from glazing material mixed in the concrete, and a coating on said glaze.

3. An article formed fromcementitiousmaterial, cellular burned shale and a glazing material, said article having a glaze formed from the glazing material exposed on a sury face thereof.

4. article formed from cementitious material, a cellular aggregate and a glazing material, said article having a glaze formed from the glazing material exposed on a surface thereof.

5. An article formed from cementitious material, a cellular aggregate and a glazing material, said-article having a glaze formed from the glazing material exposed on a surface thereof, and a coating on said glaze.

In testimony whereof, we hereunto ailix our names this 29th day of September, 1930.

PETER J. MAUL. MARTIN HOFFMAN. 

